Steam-turbine.



N0. 806,298. i 1 PATENTED DEC.A 5, 1905-.

J. wpslvrITH- y .A STEAM TURB-INE.

'APPLICATION FILED JAN. 27. 1965.

mm llllllllllll v ffy@ UNITED STAT-Es,

[PATENT OFFICE.

JOHN W. SMITH, OF ERIE, PENNSYLVANIA.

ysTl-:Awl-TuREINE.`

l No. 806,298.

Speccation of Letters Patent.

Patented Dec. 5, 1905.

Appumiion ned January 27,1905. serial No. 242,904..4

To a/ZZ whom it may concern:

-Be it known that I, JOHN W. SMITH, a citizen of the United States,residing at-Erie, in

' 777 ,313, issued to me December 13, 1904, and

to an application for a patent tiled January l2, 1905, under Serial No.240,7 50, to which reference is here made. These inventions relate to asystem of guiding the steam from the steam-inlet to the steam-outlet ofthe casing in a spiral path with that part of the path Which thesteam-path takes from the outlet ends of one series of buckets to theinlet ends of the next series of buckets of gradually-increasing size.

This invention relates to an improvement over this system in that thesteam is guided also in a spiral path from the steam-inlet tothefsteam-outlet of the casing, but that each part of the pathconnecting the outlet ends of one series of buckets with the inlet endsof the next series of buckets is of the same crosssection throughout itslength, each successive path, however, being of greater cross-sectionand of greater size than the preceding one.

For this purpose the invention consists of a steam-turbine comprising acasing having steam-inlets and steam-outlets, a turbine- Wheel, aplurality of buckets thereon, and means adapted to receivethe steamemanating from the outlet ends ofthe bucke-ts and to guide the same intothe inlet ends of the next series of buckets, causing the steam to.partakeof a spiral path from the steam-inlet to the steam-outlet of thecasing, said means being so arranged that the part connecting the outletends of one series of buckets with the inlet ends oi' the next series ofbuckets is of larger size than the preceding part, each part being ofequal cross-section' throughout its length; and the invention consists,further, in certain-novel features and combinations of parts which willbe fully described hereinafter and finally pointed out in the claims.

In the accompanying drawings, Figure l represents a development pf aportion of my improved steam-turbine, showing the buckets, the guidechannels or chambers, admis- 4sion-bladesi-or directing the steam intothe inlet ends of the buckets and curved releaseblades adapted to directthe steam emanating from the outlet ends of the buckets into and throughthe guide channels or chambers, each of said guide channels or chambersbeing of' larger size and greater cross-section than the preceding one,but each having the same crosssection throughout' its length. Fig. 2 isa vertical transverse section of the casing and the turbine-wheel, takenon line 2 2, of Fig. l', showing the division-wall of the bucketssecured to the turbine-wheel. a development of a portion of a modifiedform of my improved turbine having two inlet-l nozzles and showing thebuckets, the guidechannels and admission-blades in the guidechannels fordirecting the steam tothe inlet ends of the buckets and showing clearlythe guide-channels each of a greater size than the preceding one Fig. 4shows a development of a portion of a modi-fied form of my improvedturbine having a single inlet-nozzle and no admission-blades, and Fig. 5is a vertical transverse section of Fig. 3,taken on line 5 5 and showingclearly the guide-channels, one being of larger size than the other.

Similar letters of reference indicate corresponding parts. l

Referring to the drawings, andA more par- Fig. 3 shows ticularly to Fig.1, C represents a casing pro- 'f vided with a steam-inlet E. Arepresents a turbine-wheel of an axial-flow turbine embodying myinvention which is provided at its periphery with a plurality of curvedbuckets B. These `buckets B are formed by mortising curved channels inthe turbine-wheel. They may be of the same cross -sectional areathroughout their lengths. They may be circular or rectangular incross-section, or the mortised -channels may have'their inlet and outletends of rectangular cross-section and their central part rectangular incross-section with rounded corners or approximately circular. Thesechannels may belinedwithclosed tubes of proper shape or may be leftsimply as such, as shown in the drawings, and division-walls providedadapted to form,with the channels, buckets. In case detachable tubularbuckets are used. or in such other cases where it is deemed advisable,the casing C is at its lower end on a plane with the inlet and outletends of the buckets, as shown in Fig. 2, and the turbine-wheel isprovided with a ring R, secured thereto, so that the space between thewheel A and the ring R forms the buckets proper.

In a preferable form of bucket construction (shown in Figs. 3 and 5) thecasing C is provided at its lower end with adownwardly-extending curvedportion R and the turbinewheel provided notalone with the series curvedchannels, but with a circular channel concentric with its periphery, bymeans of which the turbine-wheel may be rotated without being obstructedby the extension, while the space between the extension and the turbineforms the buckets proper. The buckets are so arranged that the steam isdischarged parallel to, but in a direction opposite to the enteringsteam.

The casing C-(shown in Fig. l) is provided with partitions D, D', andD2, parallel to each other, which divide the casing into chambers, eachchamber having at each point the same cross-sectional area, one chamberbeing larger or of greater cross-section than the preceding one. Steamenters the casing C by the steaminlet E and is directed by theadmission-blades F into the steam-inlet ends of a series of buckets B.The steam impinging against the buckets expends part of its energy inimpulse and reaction and so in propelling the turbinewheel onwardlyconverts that part of its energy into useful work. The steam emanatingfrom the outlet ends of the buckets enters again the casing immediatelyabove the outlet ends of the buckets, being received by a chamber formedby the casing and partitions D and Dl and' so formedas to be of the samecross-section at every point throughout its length. This channel orchamber directs the steam back toward the inlet ends of the next seriesof buckets B and then, by means of the admission-blades F, into theinlet ends of the buckets, where the energy resident in the same isagain converted to useful work in propelling the wheel onwardly. Thissteam passing through the buckets and emanating from the outlet ends ofthe same enters the inlet end of the next chamber formed by the casingand partition-walls D and D2 and is directed by this chamber to theinlet ends of the next series of buckets, from the outlet ends of whichit emanates and passes into a suitable condenser or exhausts into theatmosphere. The chamber formed by the walls of the casing C andpartitions Dl and D2 is also vdownwardly in proximity to the inlet endsof the bucket-s, as well as the admission-blades, are tapering in shape,so as to insure an eliicient entrance velocity of the steam enteringthebuckets. Those parts of the partitions extending downwardly intoproximity to the outletends of the buckets are scoop-shaped at theirlower ends, and intermediately between the partitions are arrangedscoopshaped or curved release-blades G for the purpose of giving thesteam a forward turn and so directing the steam forwardly toward theoutlet end of the chamber.

In Fig. 3 is shown a modified but preferable form of my improvedturbine, which is especially adapted for the use of gas as a motor Huid.A radial-flow turbine is shown; but the novel features herein describedand hereinafter to be claimed apply equally well to axial-flow turbines.The turbine-wheel A is provided with a plurality of channels into whichthe downward extension R protrudes, so as to form, with theturbine-wheels, buckets, as shown clearly in Fig. 5. By the steaminlet Ethe steam enters two nozzles H and H somewhat contracted incross-sectional area at their upper end, and the walls of which divergetoward the inlet ends of the buckets. These nozzles are parallel withthe channels and of a cross-sectional shape similar to that of thechannels. They direct the steam into the inlet ends of the buckets, fromthe outlet ends of which the steam enters the inlet end of a channel Mof the casing, which channel is at every pointthroughout its length ofthe same cross-sectional area and serves to direct the steam after beingsubdivided, by means of admission-blades F', into the inlet ends of thenext yseries of buckets. The turbinewheel is thereby propelled onwardlyand the steam emanating from the outlet ends of these buckets enters theinlet end of the next channel M/ of the casing, which channel is also atevery pointthroughoutits length of the same cross-sectional area, but oflargersize both in cross-sectional area and in height than the channelM. The channel M directs the steam again back to the inlet ends of thenext series of buckets against which it impinges, and thereby propelsthe wheel onwardly and from which it emanates and enters either asuitable condenser or exhausts directly into the atmosphere. Those partsof the casing which IOO IIO

separate one channel from the other and which extend downwardly inproximityto the outlet ends of the buckets are scoop-shaped, as shownclearly in Fig. 3. No curved releaseblades are shown; but, if it isspecially desired, such may be used. It is seen that the steam passingfrom the steam-inlet succes-l .tracted step by step as it comes incontact with each separate series of buckets. A

In Fig. 4 is shown another modied formof 'my improved turbine alsoadapted for theuse of gas as a motor uid and having the admissionbladesand release-blades omitted. The inletnozzle H2, in communication withthe steaminlet E of the turbine, is contracted in crosssectional area at'its upper end and its walls diverge, so as to direct the motor Huidinto the first series of buckets. Fromthe outlet ends of these bucketsthe motor fluid passes into the'inlet end of the'lirst channel N ofequal cross-section throughoutits lengthv and guided by the same isdirected into the inlet end of the next series of buckets, a drop` inthe velocity of the motor fluid having, due to the expending of part ofthe energy of the motor fluid in work of impulse and reaction,

' taken place. From the outletends of this vseries .of buckets the motorfluid emanates and enters the next channel N, also ofvequalcross-section throughout its length, but, of-

larger size-that is, greater length and greater cross-section-than thechannel N, through which the motor iuid Erst passed, this largerchannel. corresponding in cross-section to the different velocity of the4motor liuid. `The last-named channel guides the motor Huid into thenext series of buckets through which it passes, propelling theturbine-wheel onwardly and from which it finally enters into a suitablecondenser or exhausts directly into the.

atmosphere. The steam in passing from the steam-inlet to thesteam-outlet of the casing successively'through the series of bucketsand channels partakes of a spiral path. The form of turbine showninyFig. 4, of which a transverse section is not shown, has itscasingprovided with a downwardly-extending divisionwall R', similar tothat hereinabove described and shownin Figs. 3 and 5. v That part of thecasing separating one channel Jfrom the other and in proximity to theoutlet ends of the buckets is tapering in shape, but may; also be 'madescoop-shaped, as shown in Fig. 3.

Complete acceleration takes.

In some cases itl is onlyneces'sary to use one f spiral path, while inother cases it would be necessary to*k use two, depending in number onthe drop or reduction in velocity of the motor fluid. One velocityreduction takes place when the motor fluid is admitted by the divergingnozzle, and a velocity reduction takes place for each separate channel.-Hence in the turbine shown three velocity reductions take place.Aturbine may be constructed having any number of velocity reductions,and also a turbine may be constructed in which the steam entersseveralsteam-inlets at once, each separate stream partaking of a spiralpath from the steam-inlet -to the steam-outlet and each streamsimultaneously passing through chambers successively greater incross-section, de-

pending on the drop in velocity', but each chamber of equalcross-section throughout its length. n

Reference has been made to the casing as one belonging to the separateunits shown in the drawings. A turbine having one or more steam-inlets,and consequently one ormore units, as shownA in the drawings, would be4provided wlth 'a mam casing surrounding both the units andturbine-wheel.

I do not wish to be understood that the channels must be exactly of the.same cross-sectional area throughout, it being within the scope ofmyinvention to use channels of substantially the, same cross-sectionalarea throughout. In practice I have found it ad- =visable to somewhatround ofi' the vcorners of the channels of rectangular cross-section at'the central part intermediately between the ends of the same, wherebyin case of channelsof smaller size the cross-section becomes somewhatelliptical.

UnitsI of larger sizes are made by casting ,from metal with coredchannels, rectangular attheir inlet and outlet ends, withrounded-offcorners at their central portion, the rectangular passagesconforming with the arc of the bucket circle.

Units of smaller sizes may be constructed by bending tubes to formthe'spiral channel, forming the ends of these tubes into rectangularshape, with the central portion `left somewhat elliptical.

In all cases where channels of rectangular cross-section are used theinlet and outlet itial'ly the same cross-sectional area throughout,adapted to guide the steam from the outlet ends of a number of bucketstothe inlet IOO IZO

ends of buckets in proximity thereto and of the same series.

2. A steam-turbine, comprising a casing, a turbine-Wheel having a seriesof buckets, and means of the same cross sectional area throughout,adapted to guide the steam from' the outlet ends of a number of bucketsto the inlet ends of buckets in proximity thereto and of the sameseries, the means connecting each successive number of outlet and inletends being of larger size than the preceding means.

3. A steam-turbine, comprising a casing, having a series of channelseach of the same cross-sectional area throughout its length, and aturbine-Wheel having a series of buckets, with their ends incommunication with the ends of the channels.

4. A steam-turbine, comprising a casing, having a series of channels ofrectangular cross-section, each of the same cross-sectional areathroughout its length, and a turbine- Wheel having a series of buckets,With their ends in communication with the ends of the channels.

5. A steam-turbine, comprising a casing, having a series ot' channelseach of different size, and each of the same cross-sectional areathroughout its length, and a turbine-Wheel having a series of buckets incommunication With the ends of the channels.

6. A steam-turbine, comprising a easing, having a series of channels ,ofrectangular cross-section, each of different size and each of the samecross-sectional area throughout its length, and a turbine-wheel having aseries of buckets with their ends in communication with the ends of thechannels.

7. A steam-turbine, comprising a casing, having a steam-inlet and aseries of channels, each of the same cross-sectional area throughout itslength, a nozzle in said casing in communication with the steam-inlet,parallel With said channels, and a turbine-wheel having a series ofbuckets with their ends in communication With the ends of the channels.

8. A steam-turbine, comprising a casing, having a steam-inlet and aseries of channels, each of the same cross-sectional area throughout itslength, a nozzle having divergent Walls in said casing, in communicationwith the steam-inlet and parallel with said channels, and aturbine-Wheel having a series of buckets With ends in communication withthe ends of the channels.

9. A steam-turbine, comprising a casing, having a steam-inlet and aseries of channels, each of the same cross-sectional area throughout itslength, a plurality of nozzles in said casing in communication withsaid-steam-inlet, and a turbine-Wheel having a series of buckets withends in communication with the ends of the channels.

10. A steam-turbine, comprising a casing, having a plurality of channelseach of different size, and each of the same cross-sectional areathroughout its length, a plurality of admission-blades in said channels,and a turbinewheel having buckets.

11. A steam-turbine, comprising a casing having a plurality of channelseach ot' different size, and each of the same cross-sectional areathroughout its length, a plurality ot' admission blades, a plurality ofcurved releaseblades, and a turbine-wheel having buckets.

12. A steam-turbine, comprising a casing having a plurality of chan nelseach of the same .cross-sectional area throughout its length, a

turbine-Wheel provided with curved channels, and a division-wall formingbuckets with the channels of the turbine-wheel.

13. A steam-turbine, comprising a casing havingaplurality of channels,each of the same cross-sectional area throughout its length, aturbine-Wheel provided with curved channels, and a beveled division-wallforming buckets with the channels of the turbine-wheel.

14. A steam-turbine, comprising a casing having a plurality of channels,each of the same cross-sectional area throughout its length, aturbine-Wheel provided with curved channels, and a stationarydivision-wall forming buckets with the channels of the turbine-wheel.

15. A steam-turbine, comprising a casing having a plurality oi'rectangular channels, each of different size and each of the samecross-sectional area throughout its length, a turbine-Wheel havingcurved channels, and a division-wall forming buckets with the channelsof the turbine-wheel.

16. A steam-turbine, comprising a casing having a steam-inlet and anexhaust, a plurality otl channels each of different size and each of thesame cross-sectional area throughout its length, and a turbine-wheelhaving buckets, said channels being adapted to guide the steam emanatingfrom the outlet ends of one series of buckets, to the inlet ends of thenext series, so as to cause the steam, passing successively through thechannels and buckets to partake of a spiral path from the steam-inlet tothe exhaust.

17. A steam-turbine, comprising a casing, having a steam-inlet and aseries of channels, each of the same cross-sectional area throughout itslength, a nozzle of cross-sectional shape similar to that oi' thechannels in said casing, in communication with the steam-inlet, and aturbine-Wheel having a series oi' buckets With their ends incommunication with the endsof the channels.

18. A steam-turbine, comprising a casing, having a steam-inlet and aseries of channels of rectangular cross-section, each of the samecross-sectional area throughout its length, a

IOO

, `nozzle rectangular in cross-section in said cas- 19. A steam-turbine,comprising a plurality.

of units, one'adjacent the other, each consistlng of a casmg havlng,` asteam-lnlet anda serles of channels, each of the same cross-see- 10tional area throughout, and a turbine-Wheel With a series of bucketshaving" their ends in communication With the ends of the channels. Intestimony that I claim the foregoing as my inVentionI have signed myname in presence of tWo subscribing Witnesses.

'JOHN W. SMITH.

Witnesses:- y

ROBERT BRANKSTONE,. P. VIGIEFORD.

